Keywords:
Radioprotection / Radiation dose, Radiographers, Professional issues, CT, Radiation safety, Quality assurance
Authors:
R. M. S. C. Pereira, A. B. Ribeiro, A. I. S. Ferreira, H. Pinto, S. Carvalho, M. Santos; Aveiro/PT
DOI:
10.1594/ecr2018/C-1736
Conclusion
Regarding the obtained results we concluded that there is a strong variability in the head positioning,
based on the diffused variability of the relation between gantry tilt and scan angle,
explained in part by the patient´s age and its neck mobility.
As expected,
it was also possible to conclude that the posterior fossa range has a great influence on the total dose exposure of the patients submitted to routine head CT when compared with the supratentorial ranges.
So,
it makes this range a good target to optimize dose exposure in routine Head CT.
In this health facility,
even there is a great range of scan angles,
the larger part of the sample was studied with scan angles between orbitomeatal and supraorbitomeatal orientation.
Regarding at the results obtained in the patient sample and strengthened with the phantom assay we concluded that gantry tilt only has influence in head CT exposure dose if a standardized patient positioning was achieved,
and it was not possible for all patients.
In continuity with the above,
we concluded that scan angle it is what really influences the dimension of the acquisition ranges,
with more impact in the posterior fossa range,
consequently the DLP value of this range and total DLP and therefore the exposure dose.
Like this,
scan angles close to supraorbitomeatal orientation reduces the exposure dose of patients submitted to routine head CT studies.
Briefly,
based on the results obtained,
we concluded that radiographer should have a special attention to the posterior fossa range and use supraorbitomeatal scan angles orientation in order to reduce the total exposure dose of the patients submitted to routine head CT. Based on the literature,
this orientation will also reduce the lens eyes dose exposure.
So the radiographers,
in their practice,
to reduce exposure dose of the patients submitted to routine head CT should adapt the optimization of the scan angle orientation in order to reduce posterior fossa dimension.